Bus 2.0l vs 1.7 914 Motor Dilemma Options

[Montroe]

I recently purchased a 74 914 with what I thought was a 1.8l engine with low compression on all 4 cylinders. My plan was to get the heads cleaned up and have new valves and guides installed and replace the pistons and cylinders with a 94mm set. After removing the engine, I found that the block does not have ID numbers in either location, the heads are 2.0l bus heads 022 101 372G and the pistons and cylinders are 94mm. If it is a bus block, the dipstick has been relocated. I also have a 1.7l long block W0093163 with 022 101 372 heads that is also in need of refreshing. So, should I have larger valves (42mm/37.7mm) installed in the unidentified (possibly bus) block and go with 96mm P&C's or go with the 914 1.7l block and have the heads opened up to accept 96mm P&C's and maybe have larger valves installed as well? Either setup will be fed by Weber 40 IDF carbs. Thanks in advance for the advice.

[914Sixer]

Use the 1.7 block and the rest of the 2.0 bus parts. All the internals are interchangeable. You can use 96 mm PC because they are slip in. Use the bus heads. You do not say what you are using for fuel.

[Montroe]

Use the 1.7 block and the rest of the 2.0 bus parts. All the internals are interchangeable. You can use 96 mm PC because they are slip in. Use the bus heads. You do not say what you are using for fuel.

Thanks for the response. I was planning to use regular 89 octane unleaded. Is there a reason to use premium?

[porschetub]

Use the 1.7 block and the rest of the 2.0 bus parts. All the internals are interchangeable. You can use 96 mm PC because they are slip in. Use the bus heads. You do not say what you are using for fuel.

(IMG:style_emoticons/default/agree.gif) and hear the 1.7(W0) block is the good one to use ,have a good one in my collection,bus cases get a much harder time,seen a lot of cracked heads on these to due to overheating also.
Be aware fitting larger valves needs to be done by a very experienced shop,the average engine rebuilder has no idea of how to fit new seats in aircooled heads.

[Bob L.]

Use the 1.7 block and the rest of the 2.0 bus parts. All the internals are interchangeable. You can use 96 mm PC because they are slip in. Use the bus heads. You do not say what you are using for fuel.

Thanks for the response. I was planning to use regular 89 octane unleaded. Is there a reason to use premium?

I think he meant fuel injection/carbs/microsquirt

[Montroe]

Thanks for the info guys. I'm running Weber 40 IDF carbs.

[larryM]

- the 2.0 bus heads have a different "square" exh port - won't match up to 914 headers

you will have to make custom exhaust

otherwise it's a cheap & easy way to have a 2.0

Use the 1.7 block and the rest of the 2.0 bus parts. All the internals are interchangeable. You can use 96 mm PC because they are slip in. Use the bus heads. You do not say what you are using for fuel.

[jcd914]

The earlier 2.0L bus heads are "oval port", the same as 914.
Not sure when the change over to "square port" heads (really rectangular ports)
My 78 2.0L bus had the "oval port" heads although some parts sources indicated they should have been "square port" heads.

Jim

[Montroe]

Thanks LarryM and JCD914. My 2.0l bus heads have oval ports.

[McMark]

Use either case (depending on which one is in better shape).
Use the 2.0 crank and rods.
Get new AA 96mm pistons and cylinders.
Get a cam from the Type4Store.
Get new 2.0 bare heads from AA and have them assembled by someone who knows T4 heads.

[porschetub]

The earlier 2.0L bus heads are "oval port", the same as 914.
Not sure when the change over to "square port" heads (really rectangular ports)
My 78 2.0L bus had the "oval port" heads although some parts sources indicated they should have been "square port" heads.

Jim

Have seen oval port heads from 2 litre bus I have one in my stash,if I remember correctly they have rather small valves compared to the 914,the 1.8 bus heads seem to have largest valves of the bus heads I have got.
All the bus heads I have are from ROW carbed engines so there may be a difference in spec to the US ones.

[Montroe]

The earlier 2.0L bus heads are "oval port", the same as 914.
Not sure when the change over to "square port" heads (really rectangular ports)
My 78 2.0L bus had the "oval port" heads although some parts sources indicated they should have been "square port" heads.

Jim

Have seen oval port heads from 2 litre bus I have one in my stash,if I remember correctly they have rather small valves compared to the 914,the 1.8 bus heads seem to have largest valves of the bus heads I have got.
All the bus heads I have are from ROW carbed engines so there may be a difference in spec to the US ones.

Thanks for the response my friend. The heads are currently at a local shop (Xtreme Cylinder Heads) in Palm City, FL being rebuilt with 42mm intake and 36mm exhaust valve. Xtreme specializes in air cooled Porsche and VW heads. Estimated cost is between $500-$600 for the work plus the cost of the valves and springs which I will provide. I ordered the valves and springs from European Motorworks in Hawthorne, CA.

The original valves were 37.5mm and 33mm so you're right, rather small for my application.